knb-lter-sev.152.480570

Summary Information

Soil Nutrient Distributions in Chihuahuan Desert Grasslands and Shrublands at the Sevilleta National Wildlife Refuge, New Mexico (1989)

Creator:
Individual:	Anne Cross
Organization:	SEV LTER

Publication Date:

2011

Language:

english

Abstract:

Vegetation throughout the southwestern United States has changed from perennial grassland to woody shrubland over the past century. Previous studies on the development of 'islands of fertility' focused primarily on only the most limiting, plant-essential element, soil nitrogen (N). The research presented here addressed the question of whether other plant-essential elements, namely phosphorus (P) and potassium (K), showed similar concentration gradients under the desert shrub Larrea tridentata (creosotebush). It also examined whether the spatial distribution of N, P, and K differed from that of essential, but non-limiting nutrients, namely calcium (Ca), magnesium (Mg), and sulfur (S), and non-essential elements, namely sodium (Na), chloride (Cl), and fluoride (F). Within adjacent grassland and shrubland plots, surface soils were collected under and between vegetation and analyzed for a suite of soil nutrients. Soil nutrient distribution followed a uniform pattern that mirrored the spatial homogeneity of bunchgrasses in the grassland, but followed a patchy distribution that mirrored the spatial heterogeneity of individual shrubs in the shrubland. The main differences were that in the grassland, all elements were uniformly distributed, but in the shrubland the plant-essential elements, nitrogen, phosphorus, and potassium, were concentrated under the shrub canopy, and the non-limiting and non-essential elements were either concentrated in the intershrub spaces or were equally concentrated under shrubs and in the interspaces. Our results show how vegetation shifts from grassland to shrubland contribute to long-term, widespread change in the structure and function of desert ecosystems.

Keywords:
Keyword:	inorganic nutrients
Keyword Thesaurus:	Core Areas

Keywords:
Keyword:	nutrients
Keyword:	soil nutrients
Keyword:	nitrogen
Keyword:	phosphorus
Keyword:	total phosphorus
Keyword:	soil
Keyword:	grasslands
Keyword:	plants
Keyword:	shrubs
Keyword:	vegetation
Keyword Thesaurus:	LTER Controlled Vocabulary

Additional Information:

Intellectual Rights:

Data Policies

This dataset is released to the public and may be freely downloaded. Please keep the designated Contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement of the Sevilleta LTER. Datasets must be cited as in the example below. Muldavin, E. 2004. Sevilleta LTER Fertilizer NPP Study Dataset. Albuquerque, NM: Sevilleta Long Term Ecological Research Site Database: SEV155. (Date of download) A copy of any publications using these data must be supplied to the Sevilleta LTER Information Manager.

Distribution:

Online:
URL:	http://sev.lternet.edu/node/2197

Coverage:

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 58

Bounding Coordinates:
West Bounding Coordinates:	-106.70657868
East Bounding Coordinates:	-106.70657868
North Bounding Coordinates:	34.32513776
South Bounding Coordinates:	34.32513776

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 55

Bounding Coordinates:
West Bounding Coordinates:	-106.70665
East Bounding Coordinates:	-106.70665
North Bounding Coordinates:	34.320378
South Bounding Coordinates:	34.320378

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 53

Bounding Coordinates:
West Bounding Coordinates:	-106.701138
East Bounding Coordinates:	-106.701138
North Bounding Coordinates:	34.320261
South Bounding Coordinates:	34.320261

Geographic Goverage:

Geographic Description:

Location: Deep Well Areasiteid: 50

Bounding Coordinates:
West Bounding Coordinates:	-106.6782
East Bounding Coordinates:	-106.6782
North Bounding Coordinates:	34.3757
South Bounding Coordinates:	34.3757

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 51

Bounding Coordinates:
West Bounding Coordinates:	-106.7038
East Bounding Coordinates:	-106.7038
North Bounding Coordinates:	34.3265
South Bounding Coordinates:	34.3265

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 52

Bounding Coordinates:
West Bounding Coordinates:	-106.7041
East Bounding Coordinates:	-106.7041
North Bounding Coordinates:	34.326
South Bounding Coordinates:	34.326

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 56

Bounding Coordinates:
West Bounding Coordinates:	-106.7301
East Bounding Coordinates:	-106.7301
North Bounding Coordinates:	34.334
South Bounding Coordinates:	34.334

Geographic Goverage:

Geographic Description:

Location: Five Points Areasiteid: 57

Bounding Coordinates:
West Bounding Coordinates:	-106.7303
East Bounding Coordinates:	-106.7303
North Bounding Coordinates:	34.3341
South Bounding Coordinates:	34.3341

Temporal Coverage:
Calendar Date:	1989-01-01

Purpose:

The research presented here addressed the question of whether other plant-essential elements, namely phosphorus (P) and potassium (K), showed similar concentration gradients under the desert shrub Larrea tridentata (creosotebush). It also examined whether the spatial distribution of N, P, and K differed from that of essential, but non-limiting nutrients, namely calcium (Ca), magnesium (Mg), and sulfur (S), and non-essential elements, namely sodium (Na), chloride (Cl), and fluoride (F).

Contact:

Position Title:

Information Manager

Organization:

LTER Network Office

Physical Address:
Delivery Address:	UNM Biology Department, MSC03-2020
Delivery Address:	1 University of New Mexico
City:	Albuquerque
Locality:	NM
Postal Code:	87131-0001
Phone:	USA

Phone:

505 277-2535

Phone:

505 277-2541

Email:

tech-support@lternet.edu

URL:

http://www.lternet.edu

Contact:

Individual:

Information Manager Sevilleta LTER

Organization:

SEV LTER

Physical Address:
Delivery Address:	1 University of New Mexico
City:	Albuquerque
Postal Code:	87131

Phone:

(505) 277-2109

Phone:

(505) 277.5355

Email:

data-use@sevilleta.unm.edu

Publication Place:

Sevilleta LTER

Method Step:

Description:

Plot establishmentFour 10 X 10-m plots were established in grassland and shrubland sites in 1989. In the grassland, two plots were located where B. eriopoda dominates and two plots were located where B. gracilis dominates. In the shrubland, paired plots were located in two shrubland areas dominated by L. tridentata.Biomass estimationAboveground plant biomass was estimated for each vegetation type at the height of the summer growing season in July 1989. Estimates of grassland biomass were based on clippings of aboveground plant material from a composite of three separate 1 m2 quadrats adjacent to each grassland plot. Estimates of shrub biomass were calculated from shrub volume measures – one height and two canopy diameter measurements – taken on all L. tridentata shrubs in each shrubland plot following Ludwig et al. (1975). Volume measurements were not taken on the few desiccated or dead individuals of the sub-shrub G. sarothrae in the plots.Ludwig, J. A., Reynolds, J. F. and Whitson, P. D. 1975. Size-biomass relationships of several Chihuahuan Desert shrubs. Am. Midl. Nat. 94:451-461.Soil SamplingTo characterize overall soil nutrient composition and soil properties, we collected 25 soil samples from 0–10 cm in depth using a stratified-random sampling design in each of the eight 10 X 10-m plots, noting whether the sample was taken from beneath vegetation or in the bare space between plants. This resulted in a total of 100 soil samples from the grassland and 100 samples from the shrubland habitats. Soil samples were taken at the height of summer drought and although they appeared dry to the touch, all samples were air dried and sieved through a standard 2 mm mesh sieve prior to analysis. Soil Nutrient AnalysisWe analyzed all soil samples for NO3-N, total N, K, total organic C, Ca, Mg, SO4-S, F, Cl, Na, and P. Ground soil samples were analyzed for total organic carbon and total nitrogen using a Carlo-Erba CHN Analyzer. Anions, except for phosphorus, were extracted by shaking a 6-g sample in 30 ml of deionized H2O for 30 min. The extract was filtered through a 0.45 um millipore filter, and analyzed with a Dionex 2010i ion chromatograph. Cations were extracted by shaking a 10-g soil subsample with 50 ml of NH4C2H2O2 (ammonium acetate) at pH 7.0. The extract was filtered gravimetrically through a #40 Whatman filter and analyzer with a Perkin Elmer 3100 Atomic Absorption Spectrophotometer. Phosphorus was extracted using a modified sequential Hedley fractionation (Tiessen et al. 1984; Tiessen andMoir 1993). A 2-g soil sample was placed in a 50 ml plastic centrifuge tube with 30 ml of deionized water and a 2.5 cm2 anion exchange membrane (AR- 204UZR-412 Ionics, Watertown, MA). Samples were shaken end-over-end for 16 h at 25 degrees C. The anion-exchange membrane was removed and phosphorus retained on the membrane was eluted by shaking the strip with 30 ml of 1 M HCl for 4 h (resin-extractable P). Subsequently,the remaining soil sample was extracted with 30 ml of 0.5 M NaHCO3 (pH 8.5) in the 50-ml centrifuge tube (bicarbonate-extractable P). This process was repeated with increasingly stronger reagents that remove more tightly bound, less plant-available, fractions using NaOH, HCl, and H2SO4-H2O2. Each sample was also sonicated and resuspended in NaOH to remove P that is otherwise encapsulated in Al and Fe minerals. All extracts were analyzed for orthophosphate with the Total Phosphorus procedure for the TRAACS 800 Autoanalyzer. Tiessen, H., Stewart, J. W. B. and Cole, C. V. 1984. Pathways of phosphate transformations in soils of differing pedogenesis. Soil Sci. Soc. Am. J. 48: 853-858.Tiessen, H. and Moir, J. O. 1993. Characterization of available P by sequential fractionation. Pp. 75-86. In: Carter, M. R. (ed.), Soil sampling and methods of analysis. Lewis Publishers, Boca Raton.

Data Table:

Entity Name:

sev152_crossions_20121024.txt

Entity Description:

Data for SEV152

Object Name:

sev152_crossions_20121024.txt

Data Format:

Text Format:

Number of Header Lines:

Record Delimiter:

\r\n

Attribute Orientation:

column

Simple Delimited:
Field Delimiter:	,

Distribution:

Online:
URL:	https://pasta.lternet.edu/package/data/eml/knb-lter-sev/152/480570/890dca22d85ef3d6e898a9e864345ba8

Coverage:

Temporal Coverage:
Calendar Date:	1989-07-01

Attribute List:

Attribute Name:

Attribute Label:

Attribute Definition:

Sample Identification Number

Storage Type:

string

Measurement Scale:

Nominal:

Non Numeric Domain:

Text Domain:
Definition:	Sample Identification Number

Attribute Name:

Plot

Attribute Label:

Plot

Attribute Definition:

Plot Number for Ann Cross Ions Study

Storage Type:

string

Measurement Scale:

Nominal:

Non Numeric Domain:

Text Domain:
Definition:	Plot Number for Ann Cross Ions Study

Attribute Name:

Block

Attribute Label:

Block

Attribute Definition:

Block in Cross Study. Designated as a lifeformNumber

Storage Type:

string

Measurement Scale:

Nominal:

Non Numeric Domain:

Text Domain:
Definition:	Block in Cross Study. Designated as a lifeformNumber

Attribute Name:

Site

Attribute Label:

Site

Attribute Definition:

Indicates whether a sample was taken under or between plants.

Storage Type:

string

Measurement Scale:

Nominal:

Non Numeric Domain:

Enumerated Domain:

Code Definition:
Code:	between
Definition:	sample taken between plants

Code Definition:
Code:	under
Definition:	sample taken under plants

Attribute Name:

Vegetation Type

Attribute Label:

Veg

Attribute Definition:

Vegetation type where data were collected.

Storage Type:

string

Measurement Scale:

Nominal:

Non Numeric Domain:

Enumerated Domain:

Code Definition:
Code:	grass
Definition:	grassland

Code Definition:
Code:	shrub
Definition:	shrubland

Attribute Name:

Flouride

Attribute Label:

Attribute Definition:

Soil Flouride content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Chloride

Attribute Label:

Attribute Definition:

Soil chloride content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Nitrate

Attribute Label:

NO3

Attribute Definition:

Soil Nitrate Content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Phosphate

Attribute Label:

PO4

Attribute Definition:

Soil phosphate content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Sulphate

Attribute Label:

SO4

Attribute Definition:

Soil sulphate content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Rubidium

Attribute Label:

Attribute Definition:

Soil Rubidium content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Sodium

Attribute Label:

Attribute Definition:

Soil sodium content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.005

Numeric Domain:
Number Type:	real

Attribute Name:

Potassium

Attribute Label:

Attribute Definition:

Soil potassium content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.5

Numeric Domain:
Number Type:	real

Attribute Name:

Magnesium

Attribute Label:

Attribute Definition:

Soil magnesium content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.5

Numeric Domain:
Number Type:	real

Attribute Name:

Calcium

Attribute Label:

Attribute Definition:

Soil calcium content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.5

Numeric Domain:
Number Type:	real

Attribute Name:

Total N

Attribute Label:

Attribute Definition:

Total soil N content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Organic C

Attribute Label:

Attribute Definition:

Soil organic C content

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Available phosphorus

Attribute Label:

Attribute Definition:

The sum of resin-extractable P and NaHCO3-extractable P

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Unavailable Phosphorus

Attribute Label:

Attribute Definition:

sum of all P fractions except resin-extractable P and bicarbonate-extractable P

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Total Phosphorus

Attribute Label:

Attribute Definition:

The sum of available P and unavailable P.

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Resin-extractable phosphorus

Attribute Label:

resin_p

Attribute Definition:

Resin-extractable phosphorus

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Bicarbonate-extractable P

Attribute Label:

bicarb_p

Attribute Definition:

Bicarbonate-extractable P

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Hydroxide-extractable P

Attribute Label:

NaOH_p

Attribute Definition:

Hydroxide-extractable P

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

P from Sonication

Attribute Label:

Sonic_P

Attribute Definition:

P from Sonication

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

HCl-extractable phosphorus

Attribute Label:

Acid_P

Attribute Definition:

HCl-extractable phosphorus

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Residual Phosphorus

Attribute Label:

Residual

Attribute Definition:

Residual Phosphorus

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

Total Phosphorus

Attribute Label:

total P

Attribute Definition:

Total Phosphorus that includes: resin-extractable P, bicarbonate-extractable P, NaOH P, P from sonication, acid P and residual P.

Measurement Scale:

Ratio:

Unit:

Custom Unit:

microgramPerGram

Precision:

0.01

Numeric Domain:
Number Type:	real

Attribute Name:

carbon to nitrogen ratio

Attribute Label:

CtoN

Attribute Definition:

carbon to nitrogen ratio

Measurement Scale:

Ratio:

Unit:

Standard Unit:

dimensionless

Precision:

0.0001

Numeric Domain:
Number Type:	real

Attribute Name:

Carbon to phosphorus ratio

Attribute Label:

CtoP

Attribute Definition:

Carbon to phosphorus ratio

Measurement Scale:

Ratio:

Unit:

Standard Unit:

dimensionless

Precision:

0.0001

Numeric Domain:
Number Type:	real

Attribute Name:

Nitrogen to Phosphorus Ratio

Attribute Label:

NtoP

Attribute Definition:

Nitrogen to Phosphorus Ratio

Measurement Scale:

Ratio:

Unit:

Standard Unit:

dimensionless

Precision:

0.0001

Numeric Domain:
Number Type:	real